相关论文: Constraints on Supersymmetric Models from Catalyti…
Supersymmetric extensions of the standard model of particle physics assuming the gravitino to be the lightest supersymmetric particle (LSP), and with the next-to-LSP decaying to the gravitino during Big Bang nucleosynthesis, are analyzed.…
Catalysis of nuclear reactions by metastable charged particles X^- opens the possibility for primordial production of elements with A>7. We calculate the abundance of ^9Be, where synthesis is mediated by the formation of (^8Be X^-) bound…
Many models of new physics including variants of supersymmetry predict metastable long-lived particles that can decay during or after primordial nucleosynthesis, releasing significant amounts of non-thermal energy. The hadronic energy…
We consider constraints on long-lived charged scalar leptons \tilde{l}^\pm in supersymmetric models, where gravitino is the lightest superparticle. We study the decay and hadronization processes of \tilde{l}^\pm. We also take into account…
Catalyzed big bang nucleosynthesis (CBBN) can lead to an overproduction of ^6Li in gravitino dark matter scenarios in which the lighter stau is the lightest Standard Model superpartner. Based on a treatment using the state-of-the-art result…
We show that the Li problems can be solved in the next-to-minimal supersymmetric standard model where the slepton as the next-to-lightest SUSY particle is very long-lived. Such a long-lived slepton induces exotic nuclear reactions in…
The discrepancy on Li^7 and Li^6 abundances between the observational data and the standard Big Bang Nucleosynthesis theory prediction has been a nagging problem in astrophysics and cosmology, given the highly attractive and succesful Big…
We investigate how late-time entropy production weakens the Big-Bang Nucleosynthesis (BBN) constraints on the gravitino as lightest superparticle with a charged slepton as next-to-lightest superparticle. We find that with a moderate amount…
We investigate gravitino dark matter scenarios in which the primordial ^6Li production is catalyzed by bound-state formation of long-lived negatively charged particles X^- with ^4He. In the constrained minimal supersymmetric Standard Model…
We investigate supergravity models in which the lightest supersymmetric particle (LSP) is a stable gravitino. We assume that the next-lightest supersymmetric particle (NLSP) freezes out with its thermal relic density before decaying to the…
The gravitino is a promising candidate for cold dark matter. We study cosmological constraints on scenarios in which the gravitino is the lightest supersymmetric particle and a charged slepton the next-to-lightest supersymmetric particle…
We investigate the so-called superWIMP scenario with gravitino as the lightest supersymmetric particle (LSP) in the context of non-standard cosmology, in particular, brane world cosmology. As a candidate of the next-to-LSP (NLSP), we…
We consider primordial nucleosynthesis in the presence of hypothetical quasi-stable doubly charged particles. Existence of $X^{--}$ with macroscopic lifetimes will lead to the formation of its bound states with $^4$He and other light…
We discuss the scenario where the gravitino is the lightest supersymmetric particle and the long-lived next-to-lightest sparticle (NSP) is the neutralino or the stau, the charged partner of the tau lepton. In this case staus form bound…
There exists a well known problem with the Li7+Be7 abundance predicted by standard big bang nucleosynthesis being larger than the value observed in population II stars. The catalysis of big bang nucleosynthesis by metastable, \tau_X \ge…
Considering scenarios in which the gravitino is the lightest supersymmetric particle and a charged slepton the next-to-lightest supersymmetric particle (NLSP), we discuss cosmological constraints on the masses of the gravitino and the NLSP…
We constrain the lifetime of thermally produced Heavy Neutral Leptons (HNLs) from primordial nucleosynthesis. We show that even a small fraction of mesons present in the primordial plasma leads to the over-production of the primordial…
The light elements up to 7Li were produced by the Standard Big Bang nucleosynthesis (SBBN) in the early universe assuming standard conditions. All observed primordial abundances of these light elements match very well the predicted ones by…
The decays of massive gravitinos into neutralino dark matter particles and Standard Model secondaries during or after Big-Bang nucleosynthesis (BBN) may alter the primordial light-element abundances. We present here details of a new suite…
We present supersymmetric scenarios with gravitino LSP and stau NLSP in the case of a non-standard model of cosmology with the addition of a dark component in the pre-BBN era. In the context of the standard model of cosmology, gravitino LSP…